Basic Objectives: To maintain the quality of research animals through control and diagnosis of diseases within research animal facilities at the Massachusetts Institute of Technology. To recognize and define abnormal physiologic conditions and comparative diseases that may be of interest to biomedical researchers. Current Research: Salmonellosis in cats and clinical manifestation of the disease in animals stressed by experimental procedures; pathogenesis of ulcerative dermatitis in the rat; the study of diabetes mellitus in the degu (Octodon degu) and normative biology. Epidemiology of infectious drug resistance in laboratory animals and potential of R plasmid transfer between antibiotic medicated animals and personnel working in the animal facility environment. Development of effective measures to promote safety and adequate decontamination of the general animal facility environment when animals are dosed with extremely potent, toxic and/or carcinogenic compounds. Evaluation of heavy metal contamination in laboratory animal feeds.